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Dedicated Mains (again)

Mike Reed said:
TER,

I AM, indeed,a pedantic English 'Master' (teacher, presumably). I'm also a (retired) teacher of English (language, not literature).

Can I point out, then, that the apostrophe is NEVER used to form plurals, as in the the greengrocer's 'APPLE'S', and in your case, the Reed's and Toy's. Additionally, unless you are an American, 'defense' is incorrect.

This is highly off-topic, though hopefully educational, so to get back in line, and to comment on a recent earthing post by MORT, adding a dedicated earth rod can be extremely dangerous. It really does depend upon what kind of earth bonding/route you have in situ; ask any competent sparks.

Yes, as far as I know, it's a legal requirement to have your dedicated mains installation connected to the EXISTING house earthing system. Mine cetainly is, or my sparks wouldn't have certified it, as he did the final connections.
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Nice to know my radar at profiling various types of personalities, though expression, appears to be working!
P.S The word "cetainly"...should be.... certainly..... while you are at it!!! ;)
Yes I also know it is a slip -a spell check mistake.
 
ter said:
Nice to know my radar at profiling various types of personalities, though expression, appears to be working!
P.S The word "cetainly"...should be.... certainly..... while you are at it!!! ;)
Yes I also know it is a slip -a spell check mistake.
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How very perspicacious of you.:) As someone said recently on this thread, there's a world of difference between typographical and spelling errors; I am beset with the former, unfortunately; a legacy of advancing years.

Not quite sure how I'd use a spellchecker, though I gather they're geared to American English, and therefore less than infallible at best.
 
Having seen Steven's install here's what i think. His system benefits from a larger and new main fuse on the incoming main and his hifi benefits from its own separate spur right back to the tails. I don't think his garden ground makes any difference, I never heard of one measuring better than the mains earth- because if it did then all the adjacent houses would earth through it too and the 'puny' wiring would quickly fry.

I'm sure it's a comfort though, and that's what's important. That his separate spur is an improvement we can put to the test tomorrow!
 
Simon, the earth in the garden was added a week after the separate spur and it made quite a significant difference, albeit a subjective one.
 
There seems to be a misconception that the earth conductor is in the circuit path - if there is more than 30mA flowing to earth, the RCD on the circuit will trip immediately. The earth is primarily for safety (as in Protection against direct contact of conductive surfaces), so who can tell me the effect of messing about with the earthing arrangement has on the performance of a piece of electrical equipment? If you open the lid of most bits of Hi-Fi, you will see the earth wire is fixed to the metal case, and nothing else.
Cheers,
Mort
 
Steven, could you really possibly tell. 30 seconds after the music is turned off you've forgotten what it sounded like. Are you honestly saying you were plugging and unplugging the garden earth as the music was playing? Like I said, it's a comfort, but as Mort pointed out there's nothing flowing through it.
 
martin clark said:
A couple of rods, even a farm full in most soils, will not come close to whatever comes in to the meter in the UK.

(If there is a sound difference it's for other reasons - I can think of a couple of technical candidates, but it way offtopic)
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I did a test dig for a reservoir in 1995 and it was dry as far as we could reach; about 10 metres.
The clay underneath that was too dry to make a decent dam as well; the closest conductive layer would have been on the bottom of the limestone at 130 metres.
 
Any ideas how to get 2 x 10 mm2 tails into the back of an MK socket ?
I tried a dress rehearsal at work and couldn`t get them to fit for love nor money !!!!

6 mm2 works fine.
 
jevy47 said:
Any ideas how to get 2 x 10 mm2 tails into the back of an MK socket ?
I tried a dress rehearsal at work and couldn`t get them to fit for love nor money !!!!

6 mm2 works fine.
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Only to 1 socket though. How do you loop them to the adjacent socket, or is it 1 radial per socket? Please don't tell me that they are only single sockets as well!
 
Having installed a dedicated mains system and experimented with earth, the best in my set up was to use the house earth with the HiFi CU very well attached and all units effectively star earthed to the CU.

I did have a separate external earth and this was better with the old mains set-up which is still in place so I can a-b for old earth (through the house to the incoming earth), spike in the garden, dedicated mains, old mains.

Using the old mains a dedicated earth made a difference, on the new a clean connection to the incoming fortunately was better. There are issues with external separate earths with mains theory, thankfully a very good connection to I suspect a better earth than watered spike was better.
 
jevy47 said:
Any ideas how to get 2 x 10 mm2 tails into the back of an MK socket ?
I tried a dress rehearsal at work and couldn`t get them to fit for love nor money !!!!

6 mm2 works fine.
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What's the problem? 10mm goes into a single (or double) MK socket; at least it did a few years back, but maybe they've changed.

Sure, it's a squeeze, but it does (did?) go. If you have two radials, I'd imagine you have two double (unswitched) sockets for convenience.
 
Earthing aside, if the ring main that serves your hifi is on a different ring to the kitchen which has all the fridges, freezers, microwaves and fluorescent lighting, how can the mains possibly benefit from a separate circuit? Surely if you have interference from the kitchen or even a neighbours circuit, installing a bloomin great radial won't cure that.
 
Pete the Feet said:
Earthing aside, if the ring main that serves your hifi is on a different ring to the kitchen which has all the fridges, freezers, microwaves and fluorescent lighting, how can the mains possibly benefit from a separate circuit? Surely if you have interference from the kitchen or even a neighbours circuit, installing a bloomin great radial won't cure that.
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Not sure I follow this. Yes, it's possible to have your hifi on a separate ring main (i.e. a dedicated ring main) to the domestic one, and a few people do, but you're STILL plugging everything into one cable.

Surely MUCH better to have radials; even ONE radial with a star-earthing hydra of some sort, although I favour multiple radials for flexibility and separation. After all, the only extra cost over one radial is the RCBO and peanuts for the cabling and extra sized c.u. box.

As for immunity to appliance interference (boilers, fridges etc.), there is certainly a big diminution, if not absolute immunity; after all, some interference is air-borne. I rarely get any, and that only from my 25 year old boiler on the odd occasion, and that's hardly noticeable on the moving coil r/player circuit, which is the only source which suffers thus.
 
So, Mike, you are saying that the sparate radials you have has removed all conducted interference on your system? This sounds like I could do with something along these lines to solve my "neighbour" problem (see "Shaken Faith" thread); Are the radials all the same length? on a diferent CU, etc? Was immunity from interference the prime reason for fitting the dedicated mains? Or is there a big SQ improvement to be had as well?
Cheers,
Mort
 
Mort said:
So, Mike, you are saying that the sparate radials you have has removed all conducted interference on your system? This sounds like I could do with something along these lines to solve my "neighbour" problem (see "Shaken Faith" thread); Are the radials all the same length? on a diferent CU, etc? Was immunity from interference the prime reason for fitting the dedicated mains? Or is there a big SQ improvement to be had as well?
Cheers,
Mort
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MORT,

Shall reply in depth later today.
 
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